The Transgenic Core Facility (TCF) is located within the Comparative Biology Facility at Pennington Biomedical and currently produces mice for COBRE investigators and other faculty at Pennington Biomedical as well as investigators at other institutions. The core utilizes pronuclear microinjection and embryonic stem cell technologies to control gene expression in mice. The objective of the TCF is to make high quality transgenic and gene knockout mouse production readily accessible, both technically and financially. The TCF, although not formally supported by the COBRE in the previous funding cycles, has been providing mouse models to COBRE scientists for several years. These models have been crucial reagents to allow COBRE scientists to be competitive in obtaining external funding (Table E1). For this next funding cycle, the COBRE will formally establish support for state-of-the-art methods in transgenic technologies to allow continued growth of methods and services. These new tools produced by the TCF will be highly effective translational models for the essential pre-clinical proof of concept studies being conducted by COBRE faculty. More specifically for the next award cycle, we are also preparing for what appears to be the next generation of targeting strategies that do not require embryonic stem cells. Targeted genome editing using engineered nucleases has been largely fueled by the emergence of clustered, regularly interspaced, short palindromic repeat (CRISPR) technology, an important new approach for generating RNA-guided nucleases, such as Cas9, with customizable specificities. Genome editing mediated by these nucleases can be used to rapidly, easily and efficiently modify endogenous genes in a wide variety of cell types and in organisms that have traditionally been challenging to manipulate genetically. This technology has the potential to eliminate the laborious and time-consuming engineering of targeting constructs for mice, but more importantly opens the doors for gene targeting in virtually any species. This is significant because a number of COBRE faculty use rats as their preferred pre-clinical model. Our plan is to begin testing this technology in mice and then progress to rats as a model for genetic manipulation. The Specific Aims of the TCF are to: 1) To utilize transgenic and gene targeting techniques to generate mouse models that mimic human disease states, such as obesity, insulin resistance, and dysregulation of lipid metabolism, and 2) Pursue new CRISPR methods and targeting strategies based on the needs of from COBRE faculty and recipients of Pilot and Feasibility funding.